ABSTRACT

Asthma is an allergic and chronic lung disease that causes inflammation and narrows the air passages. Present study aimed to characterize the gut microbiota of asthma patients and to investigate the alteration in similarity and diversity of gut microbial composition with comparison of healthy controls. Fecal samples from fifteen patients and five healthy individuals were collected. PCR-DGGE, by using universal primers focusing V3 region of 16S rRNA gene, was performed for characterization of gut microbial composition. Sequencing of most dominant excised gel bands was done. Real-time PCR was performed to evaluate the copy numbers of dominant bacteria of gut microbiota. The results indicated that a significant diversity difference between asthma and healthy groups (*P< 0.05), was shown in DGGE profile. Similarity index was found to be lower in inter-group than intra-group that indicated a change in composition of gut flora in asthma patients. Sequencing results also indicated a change of bacterial composition between both groups. qPCR results showed a significant decrease in Bifidobacterium, Lactobacillus and Clostridium leptum sub group (*P<0.05) and non-significant decrease and increase in Bacteroides vulgatus and Peptostreptococcus productus, respectively. Summarizing all, in asthma patients, there is a significant change in the molecular characterization of gut microbiota.